Jet propelled air cushion monorail vehicle

ABSTRACT

An air propelled vehicle including one or more lengthwise arranged and articulated cars. Each of the cars defines a longitudinal open-ended downwardly opening cavity or recess for bracingly receiving an elongated monorail structure along which the cars are to be moved and the lead car includes air pump means for intaking air and discharging air under pressure rearwardly for propulsion. Further, the cars include corresponding side plenum chambers communicated with each other and outlets for discharging air under pressure into the recesses for support of the cars by a cushion of air formed between the surfaces of said cars defining downwardly opening recesses and the opposing surfaces of the monorail structure. Further, the plenum chambers are in direct communication with the compressed air discharging air of the air pump means and the rearwardly opening outlet for discharging propulsion air is provided with throttle structure whereby the amount of propulsion air being discharged may be varied.

United States Patent Inventor John Van Veldhuiun 31601 SW. 197th Ave.,Homestead, Fla. 33030 [21] Appl. No. 861,614 [22] Filed Sept. 29, 1969[45] Patented July 27, 1971 v [54] JET PROPELLED AIR CUSHION MONORAILVEHICLE 9 Claims, 11 Drawing Figs. 7

[52] US. Cl 104/23 FS, 104/23 R, 104/134 [51] Int. Cl B611! 13/08 [50]Field 01 Search 104/23, 23 F5, 134; 180/119, 120, 124, 125

[56] llelerenees Cited- UNITED STATES PATENTS 3,060,867 10/1962Holmquist 104/23 FS 3,174,440 3/1965 Cockerell... 104/134 3,233,5592/1966 Smith 104/23 FS 3,444,823 5/1969 Akmentin 3,500,765 3/1970 EastonABSTRACT: An air propelled vehicle including one or more lengthwisearranged and articulated cars. Each of the cars defines a longitudinalopen-ended downwardly opening cavity or recess for bracingly receivingan elongated monorail structure along which the cars are to be moved andthe lead car includes air pump means for intaking air and dischargingair under pressure rearwardly for propulsion. Further, the cars includecorresponding side plenum chambers communicated with each other andoutlets for discharging air under pressure into the recesses for supportof the cars by a cushion of air formed between the surfaces of said carsdefining downwardly opening recesses and the opposing surfaces of themonorail structure. Further, the plenum chambers are in direct communication with the compressed air discharging air of the air pump meansand the rearwardly opening outlet for discharging propulsion air isprovided with throttle structure whereby the amount of propulsion airbeing discharged may be varied.

PATENTEnJummn 3 595 172 SHEET 1 [1F 3 John Van Ve ldhuizlen INVESTOR.

Mm MM FM I PATENTED m2? l97i v SHEET 2 BF 3 John Van Ve/dhuizenPATENTEDJULZYIQYI 3,595,172

SHEET 3 [IF 3 la/m Van Ve/dhulken @MWW WM JET PROPELLED AIR CUSHIONMONORAIL VEHICLE The monorail vehicle has been designed to provide anovel and efficient transportation system whose individual cars'andtrains may be operated at high speedwith a minimum cost of operation ofpropulsion engines and minimum .wear of contacting surface portions ofthe monorail cars and'monorail structure. i

The monorail transportation system of theinstant invention utilizes highbypass air turbine engines for propulsion and support of the monorailvehicle from the associated monorail structure. In this mannerfrictional engagement between the monorail vehicle and the monorailstructure is substantially eliminated when the monorail vehicle ismoving at operating speeds and thereis little loss due to friction inthe actual propulsion system for the'monorail vehicle. In addition, theexhaust from the high bypass air engines may be effectively muffled inanysuitable manner and the discharge of bypass air for propulsion andthe formation of an air cushion beneath each car ofthe monorail vehicleis relatively quiet. Therefore, with substantially no direct contactbetween the monorail vehicle and the associated monorail structure,muffled engine exhaust and the utilization of bypass air for propulsionand the formation of thesupport ing air cushion beneath the monorailvehicle, the monorail vehicle may be operated with a minimum of noise. i

In addition to the utilization of highbypass air for forming asupporting air cushionbeneath the monorail vehicle, the high bypass airdischarged' to form the air cushion is directed laterally inwardly anddownwardly upon upwardly and laterally outwardly inclined surfaces ofthe associated monorail structure in a manner such that the air beingdischarged to form the air cushion alsofunctions to maintain themonorail vehicle centered relative to the associated monorail structure.

ln additionto the above features, a multicar monorail train constructedin accordance with the present invention utilizes high bypass airengines only in the lead car for propulsion and the formation of an aircushion beneath each of the cars of the train, the bypass air utilizedto form the air cushions in the cars behind the lead car of the trainbeing ducted thereto through hollow opposite side plenum chambers formedin each car of the train. Flexible boots are utilized between theadjacent ends of plenum chambers of adjacent cars for maintaining theplenum chambers in closed communication and the rear end of each plenumchamber is provided with an air ,valve for selectivelyand variablythrottling the rearward discharge of air therefrom. Also, the rearwardlyopening propulsion air outlet is provided with a forwardly facingportion having a valve opening therein and the rearwardly facingpropulsion air outlet opening is provided with air shutter means wherebythe rearward discharge of propulsion air-may be throttled, either toincrease the volume and pressure of air available to form air cushionsbeneath the various cars of a monorail train or to terminate alldischarge of propulsion air rearwardly and allow that portion of thehigh bypass air normally discharged rearwardly for propulsion to bedischarged forwardly for the purpose of braking the monorail vehicle.

The main object of this invention is to provide an efficient high-speedmonorail vehicle which will be capable of operation with a minimum ofnoise. I

Another object of this invention is to provide a monorail vehicle whichmay comprise a plurality of end aligned and articulatively coupledindividual cars each provided with means for forming an air cushiontherebeneath with air under pressure supplied by and ducted from thelead car of-the monorail vehicle.

Still another important object of this invention is to provide amonorail vehicle utilizing air under pressure not only as a propulsiveforce therefor but also to form a supporting air cushion beneath eachcar of the monorail vehicle.

Another object of this invention is to provide a monorail vehicle of theair cushion type including supporting and guide rollers for utilizationin support of the vehicle from the associated monorail while the vehicleis at, rest and moving at slow speeds.

A final object of this invention tobe specifically enumerated herein isto provide a monorail vehicle in accordance with the preceding objectswhich will conform to conventional forms of manufacture, be of simpleconstruction and easy to operate so as to provide a device thatwill beeconomically feasible, long lasting and relatively trouble-free inoperation.

These together with other objects and advantages which will becomesubsequently apparent reside in the details of construction andoperation as more fully hereinafter described and claimed, referencebeing had to the accompanying drawings forming a part hereof, whereinlike numerals refer to like parts throughout and in which:

FIG. I is a fragmentary side elevational view of the forward end portionof a monorail train system constructed in accordance with the presentinvention;

FIG. 2 is a front elevational view of the monorail vehicle disposed onthe associated monorail structure with the latter being illustrated invertical transverse section;

FIG. 3 is a fragmentary longitudinal vertical sectional view takensubstantially upon the plane indicated by the section line 3-3 of FIG.2;

FIG. 4 is a fragmentary horizontal sectional view taken substantiallyupon the plane indicated by the section line 44 of FIG. 3;

FIG. 5 is a transverse vertical sectional view taken substantially uponthe plane indicated by section line 5-5 of FIG. 3;

FIG. 6 is a transverse vertical sectional view taken substantially uponthe plane indicated by section line 6-6 of FIG. 4;

FIG. 7 is a fragmentary enlarged horizontal sectional view illustratingthe manner in which flexible boots are utilized to maintain closedcommunication between the front and rear ends of opposite side plenumchambers of adjacent cars of the monorail vehicle; i

FIG. 8 is a fragmentary transverse vertical sectional view illustratingthe manner in which the air suppliedto form an air cushion beneath thecars disposed rearward of the lead car of the vehicle may be throttled;

FIG. 9 is a fragmentary transverse vertical sectional view illustratingthe left-hand air flap of FIG. 6 disposed at the rear end of the leftplenum chamber of the lead car in a partially open position; 7

FIG. 10 is a fragmentary longitudinal vertical sectional viewillustrating the manner in which the propulsion air outlet may be closedand the propulsion utilized to brake the monorail vehicle; and

FIG. 11 is a fragmentary transverse vertical sectional view similar tothe lower left-hand portion of FIG. 6 but illustrating a slightlymodified form of monorail vehiclev to be utilized in conjunction with amonorail structure whose longitudinal edges are rounded as opposed tobeveled.

Referring now more specifically to the drawings, the numeral 10generally designates a monorail structure including end aligned andjoined downwardly opening channel-shaped rail sections 12 supported inelevated position above a suitable support surface (not shown) by meansof integral longitudinally spaced opposite side legs or standards 14.The rail sections 12 include flat upper surfaces 16 and substantiallyvertical opposite side surfaces with angled or beveled surfaces 20extending between adjacent longitudinal marginal portions of thesurfaces 16 and 18. The monorail structure may be constructed of anysuitable material such as various cementitious materials.

The monorail vehicle of the instant invention is referred to in generalby the reference numeral 22 and includes a lead car 24 and a pluralityof other cars 26 disposed in end aligned relation behind the lead car24. Adjacent ends of the lead car 24 and the other cars 26 are coupledtogether in any convenient manner (not shown) and it is to be understoodthat each of the cars 24 and 26 may have provisions therein forpassengers.

The lead car 24 includes a forward driver's compartment 28 provided witha windshield 30 and the interior of the lead car 24 is partitioned intoa pair of opposite side front to rear extending engine compartments 32which open forwardly through the front end of the car 24 and areprovided with filter screens 34.

The engine compartments 32 each have a high bypass turbofan engine 34disposed therein. The engines may be of any desirable type such as theT-55 turbofan engine manufactured by Avco, Lycoming Division. Theturbofan engines 34 include fan assemblies 36 which are front mounted onthe engines 34 and mated to the power turbines thereof through a centershaft. In addition, the engine compartments are divided at their rearends into upwardly and inwardly inclined propulsion air ducts 38 andlower opposite side plenum chambers 40. The ducts 38 extend upwardlythrough the roof 42 of the lead car 24 and open rearwardly above theroof 42 as at 44. In addition, the engines 34 include exhaust gas ducts46 which extend upwardly through the ducts 38 and also open rearwardlyin closely spaced side-by-side relation as at 44.

It may be seen from FIG. 1 of the drawings that the plenum chambers 40are disposed below the floor level of the lead car 24 at least at therear end of the lead car 24 whereby an access door 48 may be provided inthe side of the lead car 24 for entrance thereinto over the associatedplenum chamber 40.

The other cars 26 are constructed similarly to the lead car 24 exceptthat they are not provided with the engine compartments 32, engines 34,ducts 38 and 46 or air intakes. Instead, the other cars 26 each includeplenum chambers 50 extending along opposite sides thereof with theforward ends of the plenum chambers 50 registered with the rear ends ofthe plenum chambers in the next forward car. In addition, it may be seenfrom FIG. 7 of the drawings, that flexible boots 52 are utilized tomaintain closed communication between the forward end of each plenumchamber 50 and the rear end of the plenum chamberdisposed in the nextforward car.

The rear end of each plenum chamber 40 has an air valve or shutter 54oscillatably supported therein for angular adjustment about a verticalaxis and a fluid motor 56 is provide for each air shutter 54 whereby thelatter may be adjustably angularly positioned, as desired. From acomparison of FIGS. 6 and 9 ofthe drawings it may be seen that the airshutters 54 may be fully closed so as to prevent the rearward dischargeof the air from the rear ends of the plenum chambers or at leastpartially opened so as to allow rearward discharge of air from theplenum chambers 40 into the forward ends of the plenum chambers 50. Inaddition, it will be noted that the rear end of each plenum chamber 50is provided with a similar air shutter 54. Also, from FIGS. 7 and 8 ofthe drawings it may be seen that each plenum chamber 50 includes ahorizontal divider plate 58 dividing the plenum chambers 50 into andupper and lower sections and that each divider plate 58 includes avertically swingable pivotally mounted flap 60 whereby the amount of airadmitted into the lower sections of the plenum chambers 50 may becontrolled. A fluid motor 62 is provided for each flap 60 whereby thelatter may be adjustably positioned as desired.

The exhaust conduits or ducts 46 open rearwardly in an unobstructedmanner and each exhaust duct 46 may be provided with suitable soundmuffling structure (not shown) if desired. Further, the rear ends of theducts 38 are provided with control flaps 66 whereby the effectivecross-sectional area of the discharge ends of the ducts 38 may be variedas desired. Any suitable means may be utilized to actuate the flaps orshutters 66.

From FIG. 3 of the drawings it may be seen that the ducts 38 includerearwardly and upwardly inclined portions 68 disposed above the roof 42and which include a pivoted flap 70 which may be swung from a closedposition illustrated in FIG. 3 of the drawings to the open positionillustrated in FIG. of the drawings. Of course, when the flaps orshutters 66 are closed as illustrated in FIG. 10 of the drawings and theflap 70 is opened, the discharge of air from the upper rear ends of theducts 38 is directed forwardly whereby a rearward thrust on the monorailvehicle 22 is provided. In this manner, the monorail vehicle may bebrakcd.

The lead car 24 includes a floor structure 72 from which longitudinallyspaced sets oftransvcrscly aligned rollers 74 are journaled. The rollers74 are recessed upwardly in downwardly opening recesses 76 formed in theflooring or floor structure 72 and only their lower peripheral portionsproject downwardly below the floor structure for rolling contact withthe upper surface 16 of the rail sections 12. In addition, the lead car24 includes similar forward rollers 78 and it is to be noted that eachof the other cars 26 also includes longitudinally spaced sets oftransversely aligned rollers such as rollers 74. From a comparison ofFIGS. 6 and 8 of the drawings it will be seen that the lower oppositeside portions of the lead car 24 and the other cars 26 is substantiallyidentical.

The plenum chambers of the vehicles 24 and 26 as well as the flooring orfloor structures of the vehicles 24 and 26 define a longitudinallyextending downwardly opening recess 80 in each vehicle 24 and 26 inwhich at least the rail sections 12 of the monorail structure 10 issnugly received. The plenum chambers aredefined by those portions of thecars 24 and 26 which depend downwardly along opposite sides of themonorail structure 10 and it may be seen that each recess 80 includessurfaces 82, 84 and 86 which parallel the surfaces l6, l8 and 20. Eachof the cars 24 and 26 includes longitudinally spaced rollers 88 atopposite sides thereof which project into the opposite side portions ofthe recesses 80 through the surfaces 84 and additional rollers 90 areprovided including peripheral portions which project through thesurfaces 86. The rollers 88 and 90 are provided for rolling engagementwith the surfaces 18 and 20, respectively. From FIGS. 6 and 8 of thedrawings it will be seen that the plenum chambers 40 and 50 includelongitudinally spaced outlets 40 and 50 which open through thecorresponding surfaces 86 for discharging air from the plenum chambers40 and 50 into the recesses 80. In this manner, an air cushion may beformed beneath each vehicle 24 and 26 as long as sufficient air underpressure is delivered to the plenum chambers 40 and 50 past the flaps 54and 60. I I

It is to be noted that the areas of the recesses 80 disposed betweenadjacent sets of rollers 74 and 78 define separate chambers in whichsupporting air cushions may be formed. The rollers 74 and 78 are closelyaxially spaced and thereby define at least partial barriers to thepassage of cushion air from one zone between adjacent sets of rollers 74and an adjacent zone. By this construction, and the utilization ofaplurality of flaps 60 spaced longitudinally along each of the other cars26, uneven fore and aft loading of the other cars 26 may be compensatedfor in order that all of the rollers 74 will be maintained out ofcontact with the upper surface 16 during normal operation of themonorail vehicle 22.

With attention now invited again to FIGS. 6 and 8 of the drawings, itwill be seen that the openings 40' and 50 are positioned so as to insurethat the air discharged from the plenum chambers 40 and 50 is directedinwardly and downwardly upon the surfaces 20. In this manner, the airbeing discharged from the plenum chambers 40 and 50 is utilized totransversely guide the monorail vehicle 22 on he monorail structure 10.

In FIG. 11 of the drawings there may be seen a modified form of monorailstructure generally referred to by the reference numeral 10' and whichis substantially identical to the monorail structure 10 except that itsupper longitudinal comers are rounded as at 110. In addition, a modifiedform of car is designated by the reference numeral 24 and the car 24includes rounded upper corners 112 of its longitudinal recess 114 whichare devoid of rollers corresponding to the rollers 86 and 88. However,the upper corners 112 are provided with upper and lower outlet openings116 and 118 for discharging air from the plenum chambers 40 of the cars24' both laterally and vertically upon the rounded comers of themonorail structure Of course, the car 24' does include rollers 74corresponding to the rollers 74 and also rollers corresponding to therollers 78.

The other cars 26 may be provided with ample accommodations forpassengers above the flooring structures 120 thereof and each car 26 maybe provided with an access door similar to access door 48. Of course,the air shutters 54 disposed at the rear ends of the plenum chambers 50of the other cars 26 are also actuated by fluid motors corresponding tofluid motors 56.

In operation, when the monorail vehicle 22 is standing still it issupported from the monorail structure 10 by the rollers 74 and 78. Afterthe vehicle 10 has been loaded, the engines 34 may be started with theflaps 66 closed and the air shutters or flaps 54 and 60 opened andadjusted in each car to compensate for the load therein. Operation ofthe engines 34 will cause the bypass air to be ducted into the plenumchambers of the cars 24 and 26 and discharged into the recesses 80 forsupport of the cars 24 and 26 on air cushions. Then, when it is desiredto move the train or vehicle 22 forwardly, the operating speed of theengines 34 may be increased and the flaps 66 may be opened in order thata portion of the bypass air will be discharged rearwardly for forwardpropulsion of the vehicle 22. As the vehicle increases speed, the eoperating speed of the engines 34 and the positioning of the variousflaps and shutters 54, 60 and 66 may be adjusted as desired so as tomaintain the cars 24 and 26 supported by cushions of air thereunderbetween adjacent sets of rollers 74 and 78.

When it is desired to slow the monorail vehicle 22, the flap 70 isopened and the flaps 66 are closed so that the discharge of bypass airfrom the ducts 38 is directed forwardly thereby applying a rearwardthrust on the vehicle 22 to slow the latter. In addition, it is alsoproposed that suitable braking means may be provided for the rollers 74and 78 and that during an emergency stop of the vehicle 22 to thebraking means for the rollers 74 and 78 may be energized aftersubstantially all discharge of air into the plenum chambers 50 isterminated and the flaps 66 and 70 have been closed and opened,respectively.

The foregoing is considered as illustrative only of the principles ofthe invention. Further, since numerous modifications and changes will'readily occur to those skilled in the art, it is not desired to limitthe invention to the exact construction and operation shown anddescribed, and accordingly all suitable modifications and equivalentsmay be resorted to, falling within the scope of the invention.

What is claimed as new is as follows:

1. For use in conjunction with an elongated monorail structure includingan upper portion having an upper surface and opposite side surfacesextending downwardly from the opposite side edges of said upper surface,an air cushion vehicle including at least a lead car and a trading careach of said cars having front and rear ends and defining a longitudinalopen ended downwardly opening recess in which to embracingly receivesaid upper portion of said rail therein, said lead car including airpump means provided with air intake and discharging means for intakingair and discharging air under pressure rearwardly for propulsion, saidlead car also including opposite side plenum chambers into which some ofthe compressed air discharged from said air pump means is bled, andbleed air discharge means for discharging the bleed air in said plenumchambers into said recess, which air supplies the lead car supportingair cushion, said trailing car being articulately coupled to the rear ofsaid lead car and also provided with opposite side plenum chambersincluding bleed air discharge means for discharging the bleed air insaid plenum chambers into said recess, which air supplies the trailingcar supporting air cushion, the rear ends of the plenum chambers openingrearwardly from the rear ends of said cars and being provided with airvalve means for variably and selectively closing the rear ends of saidchambers, and flexible boot means operatively connected between andmaintaining closed communication between the adjacent front and rearends of said plenum chambers.

2. The combination of claim 1 wherein said cars include support wheelmeans spaced both transversely and longitudinally thereof and whichinclude at least lower peripheral portions projecting downwardly intothe upper portion of said recess for rolling support of said cars fromsaid upper surface.

3. The combination of claim 1 wherein said car includes opposite sideguide wheel meansjournaled for rotation about upstanding axes and whichinclude at least inner peripheral portions projecting into the oppositeside portions of said recesses for rolling engagement with said oppositeside surfaces of said monorail structure.

4. THe combination of claim I wherein said air discharge means forrearwardly discharging propulsion air includes throttle means operativeto variably throttle the discharge of air from said air discharge meansand thus also vary the pres sure of air upstream from said throttlemeans and the amount and pressure of said bleed air available to saidplenum chambers.

5. The combination of claim 1 wherein said trailing car includespartition means dividing each of the plenum chambers thereof into twolongitudinally extending plenum chamber sections extendinglongitudinally of and opening outwardly of the opposite ends of saidtrailing car, the bleed air discharge means of said trailing carestablishing communication between said recess of said trailing car andone of said plenum chamber sections on each side of said trailing car,and said partition means including means operable to variably establishcommunication between each pair of plenum chamber sections for allowingvaried amounts of airflow between said plenum chamber sections.

6. THe combination of claim 1 wherein said bleed air discharge meansincludes means for discharging bleed air into said recess alongdownwardly and inwardly inclined paths at points spaced along oppositesides of said recess.

7. The combination of claim 1 where said bleed discharge means includesmeans for discharging bleed air into said recesses along downwardly andinwardly inclined paths at points spaced along opposite sides of saidrecesses, said elongated monorail structure including an upper portionhaving an upwardly facing upper surface and upstanding opposite sidesurfaces, said upper portion'including upwardly and outwardly facingopposite side longitudinal bevel surfaces joining said upper and sidesurfaces and disposed generally normal to and upon which said paths areincident.

8. THe combination of claim 6 including an elongated monorail structureincluding an upper portion having an upper surface and opposite sidesurfaces, said cars being disposed on said monorail structure with saidupper portion received in said recess, said upper portion includingtransversely rounded opposite side longitudinal surface portions, saidbleed air discharge means also including means for discharging bleed airinto said recess along both downward and horizontal inwardly extendingpaths on each side of each car for incidence upon the upper and lowerportions, respectively, of the corresponding rounded surface portions.

9. The combination of claim 1 wherein said cars include support wheelmeans spaced both transversely and longitudinally thereof and whichinclude at least lower peripheral portions projecting downwardly intothe upper portion of said recess for rolling support of said car fromsaid upper surface, said cars including opposite side guide wheel meansjournaled for rotation about upstanding axes and which include at leastinner peripheral portions projecting into the opposite side portions ofsaid recesses for rolling engagement with said opposite side surfaces ofsaid monorail structure.

1. For use in conjunction with an elongated monorail structure includingan upper portion having an upper surface and opposite side surfacesextending downwardly from the opposite side edges of said upper surface,an air cushion vehicle including at least a lead car and a trading careach of said cars having front and rear ends and defining a longitudinalopen ended downwardly opening recess in which to embracingly receivesaid upper portion of said rail therein, said lead car including airpump means provided with air intake and discharging means for intakingair and discharging air under pressure rearwardly for propulsion, saidlead car also including opposite side plenum chambers into which some ofthe compressed air discharged from said air pump means is bled, andbleed air discharge means for discharging the bleed air in said plenumchambers into said recess, which air supplies the lead car supportingair cushion, said trailing car being articulately coupled to the rear ofsaid lead car and also provided with opposite side plenum chambersincluding bleed air discharge means for discharging the bleed air insaid plenum chambers into said recess, which air supplies the trailingcar supporting air cushion, the rear ends of the plenum chambers openingrearwardly from the rear ends of said cars and being provided with airvalve means for variably and selectively closing the rear ends of saidchambers, and flexible boot means operatively connected between andmaintaining closed communication between the adjacent front and rearends of said plenum chambers.
 2. The combination of claim 1 wherein saidcars include support wheel means spaced both transversely andlongitudinally thereof and which include at least lower peripheralportions projecting downwardly into the upper portion of said recess forrolling support of said cars from said upper surface.
 3. The combinationof claim 1 wherein said car includes opposite side guide wheel meansjournaled for rotation about upstanding axes and which include at leastinner peripheral portions projecting into the opposite side portions ofsaid recesses for rolling engagement with said opposite side surfaces ofsaid monorail structure.
 4. THe combination of claim 1 wherein said airdischarge means for rearwardly discharging propulsion air includesthrottle means operative to variably throttle the discharge of air fromsaid air discharge means and thus also vary the pressure of air upstreamfrom said throttle means and the amount and pressure of said bleed airavailable to said plenum chambers.
 5. The combination of claim 1 whereinsaid trailing car includes partition means dividing each of the plenumchambers thereof into two longitudinally extending plenum chambersections extending longitudinally of and opening outwardly of theopposite ends of said trailing car, the bleed air discharge means ofsaid trailing car establishing communication between said recess of saidtrailing car and one of said plenum chamber sections on each side ofsaid trailing car, and said partition means including Means operable tovariably establish communication between each pair of plenum chambersections for allowing varied amounts of airflow between said plenumchamber sections.
 6. THe combination of claim 1 wherein said bleed airdischarge means includes means for discharging bleed air into saidrecess along downwardly and inwardly inclined paths at points spacedalong opposite sides of said recess.
 7. The combination of claim 1 wheresaid bleed discharge means includes means for discharging bleed air intosaid recesses along downwardly and inwardly inclined paths at pointsspaced along opposite sides of said recesses, said elongated monorailstructure including an upper portion having an upwardly facing uppersurface and upstanding opposite side surfaces, said upper portionincluding upwardly and outwardly facing opposite side longitudinal bevelsurfaces joining said upper and side surfaces and disposed generallynormal to and upon which said paths are incident.
 8. THe combination ofclaim 6 including an elongated monorail structure including an upperportion having an upper surface and opposite side surfaces, said carsbeing disposed on said monorail structure with said upper portionreceived in said recess, said upper portion including transverselyrounded opposite side longitudinal surface portions, said bleed airdischarge means also including means for discharging bleed air into saidrecess along both downward and horizontal inwardly extending paths oneach side of each car for incidence upon the upper and lower portions,respectively, of the corresponding rounded surface portions.
 9. Thecombination of claim 1 wherein said cars include support wheel meansspaced both transversely and longitudinally thereof and which include atleast lower peripheral portions projecting downwardly into the upperportion of said recess for rolling support of said car from said uppersurface, said cars including opposite side guide wheel means journaledfor rotation about upstanding axes and which include at least innerperipheral portions projecting into the opposite side portions of saidrecesses for rolling engagement with said opposite side surfaces of saidmonorail structure.